Q25 of 23 Page 15

From the prices of shares X and Y below, find out which is more stable in value:

Here


For X


Mean where n is number of terms




=


=


=


Standard deviation = √variance= √35=5.91


Coefficient of variation


For Y


where n is number of terms


=



=


=


=


Standard variance = √variance= √4=2


Coefficient of variation


Covariance of x covariance of Y


⇒ X is more variable and Y is more stable than X

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